I have a 2004 Extended Cab Silverado with 14,000 ORIGINAL miles. Whenever the temperature here in Dallas is hot, the engine/ transmission makes this loud (almost irritating whinning sound). The local Chevrolet dealership has looked at it three times now and says everything is fine. But, they went ahead and (supposedly) replaced the fan clutch just to make sure. But the sound is STILL horrible. Sounds like an 18 wheeler taking off in granny gear. The sound is so bad that whenever I pull through my office parking garage everyone turns to look at me. I am ashamed of this vehicle! No other GM vehicle has ever made this sound. My Son has a 2004 GMC Sierra (same engine and everything) and his does not make this whining sound. At first I thought it was stuck in "Tow/Haul" but that has proven not to be the case. I wish I could describe the sound better, but just imagine what a dump truck or concrete truck sounds like whenever it leaves a red light. Sounds like it is stuck in low gear (although it's not). After the engine has warmed up the sound never dissipates or goes away (well inless of course I turn the engine off). It's hard to tell if it is engine, transmission, air conditioner or fan clutch. I am at a total loss as to where the 'Granny" gear sound is coming from. The ironic part is that the dealership here in Dallas acts as though this is normal. My 2002 Avalanche did not sound like this and neither did my 1999 GMC Sierra.

I am so irritated with this and nobody seems to have a clue what it might be. I have noticed that after the vehicle has sat all night, the first few miles in the morning seems fine. But once it warms up - here comes the whine again. When the air conditioner is on it seems to sound louder than when the air conditioner is off, but just a little less.

Can anyone suggest other things the dealership could check. I KNOW this is NOT the way General Motors intended for this vehicle to sound. Thanks in advance !

 

Sounds like a bearing problem. If possible try taking the belt off when its making the noise. Check the idler tensioner pulleys they will spin free and check the alternator. It's possible it could be one or 2 bearings gone. But what is interesting is you said it's louder with the AC on which will put more load on the these bearings. Its possible that the grease has dried up in the bearings

 

I have the same problem on my 1500 Silverado 4.8 4x4. The whine has been present for 8 months now, and and is getting worse. It is present at all times when the engine is running. I have not formally taken it in to get it fixed, as of yet. I have been told by more than one person that it is probably due to a problem in the power steering pump, perhaps an air bubble in the pump/line. When the truck is stationary and in Park, the whine changes tone when I turn the wheels one way or the other. And yes, the whine is truly obnoxious and it turns heads in the parking lot.

 

sounds like the power steering pump. you could try to "chase down" the noise with a stethescope(sp?) or if you dont have one a wooden dowel rod works very well to pin point were the noise is coming from.

 

New to board and after reading realized I've heard this whine too. If I recall, I've only heard it when I'm pulling my boat in Tow / Haul. I will pay closer attention and see what I hear and when.

 

I have the same whine, gets louder as the rpms increase. Turns out to be the steering pump, the dealer said that was normal, but a mechanic friend said that the pump is going, and will need to be replaced sometime. In the mean time, he suggested I use a turkey baster, and take out as much fluid from the reservoir, and replace it with 'Lucas steering pump oil'. Seemed to help quite a bit, but the whine is still there actually, never went away completely. I think I'll have the pump replaced soon, can't stand that noise!

 

Thanks for the tips. I finally took my '02 1500 Silverado 4.8L to my mechanic after the whining got louder and louder. He said it was the power steering pump and I should try to live with it until it "goes." $440 for new pump and 4-5 hrs labor ($75 for rebuilt PS pump) and he typically charges 60% of the dealers costs. Not happy, since the truck only had 40K when the whining started. Wish there was some way to determine what percentage of Chevy trucks have this problem. Again, thanks for the feedback.

 

I have a 2002 Silverado, and the whine is there. I found a GM TSB for this. I called Chevy today, and they said it is not being looked into. The bulletin said some of the dealerships are flushing and filling the PS system with Valvoline Synthetic Fluid. I am going to try the cheap route first and just flush with conventional fluid.

 

ya i have had a couple problems with these. i replaced them on 2 2002 silverados and the noise went away.. i have draied the fluid out of my buddies truck and filled it with that lucas p/s stuff and it took the noise down quite a bit. that stuffs like chicken fat, it cures everything.

john

 

I am trying to find out the capacity of the power steering system and I can not locate info,2002 Silverado 5.3 v8 1500 I was going flush it the economical route. Undo the return line and stick it in a 1 gal milk jug and have a helper turn the wheel back and forth and dump clean fluid in the tank, I guess until the fluid looks clean.